There are many carton closures in the prior art that function to selectively close off a carton container dispensing opening. Typically, such carton containers are box-shaped and hold dry granular materials which flow freely through the dispensing opening. Such materials may include laundry detergent or the like. Also typically, the container opening is located on the side wall near its top or actually in the top.
Some prior art containers include a pour spout which is actually a separate piece from the carton board container. The spout thus described may be made of metal material such as aluminum. It is ramp-shaped and is movably fitted into the dispensing opening in the side of the container, and may be articulated from a closed position, where it is in the same plane as the container side wall, to an opened position where it forms a pour spout. A disadvantage of this prior art structure is that it requires an extra manufacturing step and additional non-carton board material. This all adds to unwanted cost.
A partial solution to the disadvantage thus posed is found in the structure shown in U.S. Pat. No. 3,438,555 issued to La Pierre on Apr. 15, 1969. With this patented device, a pour spout is formed from the carton board material of a flap extension. However, this still requires extra manufacturing steps, extra board material, and consequently extra cost.
Another type of container closure is shown in U.S. Pat. No. 3,814,301 issued June 4, 1974 to Niepman. With this container, the opening is in the top and a flap extends down over the adjacent side wall. A lateral holding nose or tab extends from the flap and engages the container. This structure has the advantage that the flap is an integral extension of the top flap. However, this structure is complicated, requires extra board material and thus is costly to manufacture.
Still another container closure of note is found in U.S. Pat. No. 1,956,238 issued on Apr. 24, 1934 to Jackson. This patent discloses a dispensing carton board container having a flap which is an extension of the top flap and which extends down over the adjacent side wall in a manner similar to the immediately preceding patent structure. However, a second flap is formed in the side wall with a fold line at the juncture with the top. This second flap is formed by making an arcuate die cut in the side wall adjacent to the top. A problem with this type of structure is that the location of the second flap at the juncture may cause weakening of the container.
A similar structure to that described immediately above is shown in U.S. Pat. No. 3,104,793 issued to Hickin on Sept. 24, 1963. Again, the location of the juncture of the second or inner flap with the top may cause weakening of the structure.